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rust-lang · Aug 24, 2020 · d9e877f · d9e877f
1 parent d04e6b8
commit d9e877f
Showing 1 changed file with 3 additions and 1 deletion.
diff --git a/library/alloc/src/collections/vec_deque.rs b/library/alloc/src/collections/vec_deque.rs
@@ -1086,7 +1086,9 @@ impl<T> VecDeque<T> {
     where
         R: RangeBounds<usize>,
     {
-        // SAFETY: This buffer is only used to check the range.
+        // SAFETY: This buffer is only used to check the range. It might be partially
+        // uninitialized, but `check_range` needs a contiguous slice.
+        // https://github.com/rust-lang/rust/pull/75207#discussion_r471193682
         let buffer = unsafe { slice::from_raw_parts(self.ptr(), self.len()) };
         let Range { start, end } = buffer.check_range(range);
         let tail = self.wrap_add(self.tail, start);